1. Field of the Invention
This invention relates to parabolic antennas and more particularly to parabolic antennas which have low wind load characteristics and parabolic antennas which are collapsible.
2. Prior art
Dish-shaped parabolic antennas are well known. Such antennas come in a variety of shapes and sizes all of which are readily identifiable by a solid dish configuration having a three-dimensional parabolic surface with a sensor mounted at the focal region of the parabolic surface.
These dish-shaped antennas have a common problem in the characteristic high wind load that is exhibited. Not only must the antenna dish itself be structurally designed to withstand high wind forces but the corresponding support structure must also be so designed. All in all, common dish-type parabolic antennas and their support structure are heavy and sturdy enough to withstand substantial environmental forces. Additionally, dish-type parabolic antennas are difficult to transport because they occupy a significant volume of space.
Some prior art approaches have attempted to minimize the wind load characteristics of parabolic dish antennas. In one approach, a wire mesh, resembling a screen, is disposed on a three dimensional parabolic surface with a support framework disposed around the periphery. In U.S. Pat. No. 3,329,960 commonly assigned with the present invention, a collapsible parabolic antenna having minimal wind load was set forth.
With the advent of home box office services and other types of communication networks, a need exists for a consumer parabolic antenna having an acceptable low price in the market place. Such an antenna should be retrofitable to the existing television antenna market place utilizing light weight support poles or masts.
The present invention recognizing the problems existing with prior parabolic antennas and recognizing the challenge facing the demand for a consumer parabolic antenna offers a solution. The present invention is a modified parabolic antenna which is fully collapsible for ease in transportation, which exhibits low wind load characteristics and which is capable of being mounted to conventional television masts as supports. Furthermore, in order to keep costs at a minimum, the present antenna minimizes the overall number of part components for ease in inventory and for low cost manufacturing. As will be pointed out subsequently, the antenna of the present invention utilizes a plurality of identically shaped reflector elements which are spaced from each other onto identical and symmetrical supports.